Planoorai ii co



O. I. DODSON.

MEANS FOR BXPLODING CHARGES.

. APPLICATION rum) APR.25,1910. Patented Apr. 30 1912.

3 SHEETSSHEET 1.

WITNESSES:

INVENTOR. 00664014/ COLUMBIA PLANOGRAPH COHWASIHNGTUN u, c,

O. I. DODSON.

MEANS FOR EXPLODING CHARGES.

APPLICATION FILED APR.25,1910. I

Patented Apr. 30, 1912.

3 SHEETS-SHEET 2.

j INVENTOR.

WITNESSlS:

G. I. DODSON.

MEANS FOR EXPLODING CHARGES.

APPLICATION FILED 151 3.25, 1910.

1,024,621 Patented Apr. 30, 1912.

3 SHEETS-SHEET 3.

WITNESSES lOfNVE/VTOR. 4 M070 A TTORNE V.

COl UMHIl-PLANOGRAPH co., WASHINGTON, D. c.

UNITED STATES PATENT OFFICE.

CHARLES I. DODSON, OF PITTSBURG, KANSAS, ASSIGNOR TO THE DODSON MANUFAC- TUBING COMPANY, OF PHOENIX, ARIZONA, A JOINT STOCK COMPANY.

MEANS FOR EXPLODING CHARGES.

Specification of Letters Patent.

Patented Apr. 30, 1912.

Application filed April 25, 1910. Serial No. 557,490.

To all whom it may concern:

Be it known that I, CHARLES I. DODSON, a citizen of the United States, residing at Pittsburg, in the county of Crawford and State of Kansas, have invented a certain new and useful Improvement in Means for Exploding Charges, of which the following is a specification.

My invention relates to improvements in means for exploding charges.

It is particularly adapted for exploding blast charges in mines.

One object of my invention is to provide an apparatus which may be easily operated and safely handled and which may be re lied upon to cause with certainty the explosion of all the charges with which it may be connected and at the pro-determined time at which the apparatus has been set for operation.

My invention provides further, an apparatus so constructed that it cannot, by means of rough usage or by accidental means, be caused to prematurely explode the charges.

My invention provides still further,means for protecting the apparatus from being tampered with by unauthorized persons.

Other novel features of my invention are hereinafter fully described and claimed.

In the accompanying drawings which illustrate the preferred form of my inven tion, Figure 1 is a vertical section on the dotted line o?) of Fig. 2, the outer casing being removed. Fig. 2 is a vertical section on the dotted line 0 cl of Fig. 1. Fig. 3 is a vertical section taken on the dotted line ef of Fig. 1, a portion of the supporting frame being broken away. Fig. 4 is a perspective view, enlarged, of the circuit controlling mechanism for short-circuiting the generator and some of the parts connected therewith. Fig. 5 is an enlarged view, partly in elevation and partly in vertical section, of the operating key and the upper end of the rack bar connected with the key. Fig. 6 is an enlarged elevation of the mechanism for holding the rack bar in the elevated position. Fig. 7 is a structural, diagrammatic view of the electric circuits, showing in solid lines the rack bar in the elevated position, supported by the holding latch. In this view the lever is shown in solid lines disconnected from the rock arm of the time piece, while in dotted lines the rock arm is shown swung to a position in whlch it engages the lever and adjacent contact spring. Fig. 8 is a diagrammatic view of the circuits, showing the rack bar held by the locking latch and the rock arm engaging the lever. Fig. 9 is a perspective view, reduced, of the apparatus, the outer casing being removed. Fig. 10 is a rear ele vation, reduced, of the apparatus, a portion of the outer casing being broken away.

Similar characters of references denote similar parts.

Referring to Fig. 10, 1 denotes a rectangular box having an open top, and having slidably inserted therein a similarly shaped inner casing 2, within which the operative parts of the machine are mounted.

3 denotes a cover, preferably arranged to slide over the open ends of the box 1, which will hereafter be called the outer casing, and the inner casing 2. Suitable means are provided for locking the cover 3 to the outer casing 1 to prevent unauthorized persons having access to the operating parts, and also for the purpose of enabling the machine to be lifted and readily transported from place to place when the handle 4:, provided on the upper side of the cover 3, is grasped.

Referring now more particularly to Figs. 1 to 8, 5 denotes a horizontal base plate, which is secured to the lower end of a vertical plate 6, the upper end of which is secured to the underside of the cover 8. WVhile in the drawings the cover 3, base plate 5, and plate 6 are shown as separate pieces they may be made in the form of a single casting. Supported on the base plate 5, forward of the plate 6, is a horizontal plate 7, upon which is mounted but electrically insulated therefrom, by a strip of insulating material 8, a time-piece 9 which is preferably of the ordinary alarm clock type, having the usual time and alarm movements, the time movement having the usual winding arbor 10 and setting arbor 11, while the alarm movement is provided with the usual setting arbor 12 and the winding arbor 13. Two upwardly extending plates 14, disposed at opposite sides of the time piece 9, have their lower ends secured to the base plate 5 and at their upper ends are secured to and support a current generator of any suitable type. As a current generator I preferably employ a mechanically operated direct-current, series wound dynamo, arranged to produce a current of comparativelyhigh amperage and low voltage. Such a machine, when in fully active condition, is more eliicient for the purpose than a machine of the magneto type but requires more time to build up a current of full efficiency. In order that the full volume of current may be produced before the current is utilized to explode the charges, I have arranged the apparatus, in its preferable form, so that the generator is short circuited during the initial part of its operation. By this means the field magnets and armature become thoroughly mag netized before the current is diverted into the main or working circuit which includes the charges to be exploded.

The generator, denoted by 15, is provided with the usual field coils 16 and 17, armature shaft 18, commutator 19, and brushes 20 and 21.

To rotate the armature shaft 18, any suitable mechanism may be employed but I prefer to employ the following described mechanism:Secured to and rotatable with the armature shaft 18, is a pinion 22, which meshes with a gear wheel 23, which may be secured rigidly or rotatably upon a horizontal shaft 24, supported in any suitable manner and having rigidly or rotatably mounted on it, at the rear side of the gear wheel 23, a pinion 25,which extends through a. horizontal opening provided therefor in the plate 6. It will, of course, be understood that if the pinion 25 is rigidly mounted on the shaft 2 lthe gear wheel 23 must be rotatably mounted thereon, and vice versa. Pivotally mounted on the rear side of the gear wheel is a pawl 26 which is held engaged with the teeth of the pinion 25 by a spring 27, secured to the gear wheel 23. Vertically slidable in suitable bearings 28, secured to the rear side of the plate 6, is a vertical rack bar 29, the teeth of which engage the teeth of the pinion 25. The arrangement of the pawl 26 is such that when the rack bar 29 is raised to the elevated position shown in Fig. 7, the pinion 25 will rotate in a direction such that the pawl 26 will slip over the pinion teeth and the gear wheel 23 will not be rotated. hen the rack bar 29, however, moves downward, the pawl 26 will lockingly engage the pinion 25, thereby rotating the armature shaft 18 through the intermediacy of the pinion 22 and gear wheel 23, thereby causing the gen orator 15 to become active for the purpose of developing a current.

For releasahly supporting the rack bar 29 in the elevated position shown in Fig. 7, until such time as has been selected for it to descend for operating the generator, I preferably employ a holding latch comprising a horizontal plate 30, horizontally slidable in suitable bearings 31, secured to the rear side of the plate 6, as shown in Fig. 3. The holdthe latch bar 30 to the left so as to release the rack bar 29, as viewed in Figs. 3 and 7, the latch 30 has pivoted to it the upper end of an upwardly and downwardly extending lever 3-:t, which is pivoted below the latch bar 30, to the rear side of the plate 6 by means of a horizontal pin For downwardly retracting the rack bar 29, I preferably employ a vertical coil spring 36, the lower end of which is secured to a raised projecting portion 37 of the base plate 5. The upper end of the spring 36 is secured to a horizontal stud 38, mounted on the rack bar 29.

To lock the rack bar 29 against any upward movement when the working circuit in which the dynamo is located is closed I pref erably employ a locking latch comprising a horizontal plate 39, one end of which is pivoted by means of a pin or screw L0 to the lever 34, below the pin 35 and the other end of which is provided with a slot -ll through which extends a guiding pin or screw s 2, extending horizontally rearward from and secured to the plate 6. The locking latch 39 is provided with a projection 1'3 which, when the rack bar 29 is in the lower position and the lever St is in the position shown in Fig. 8, will pass over and obstruct the upward movement of the stud 38.

For the purpose of swinging the lever St to the position shown in Fig. 8, and for the purpose of at the same time closing the cir cuits in which the generator 15 is located, I preferably secure to the winding arbor 13, of the alarm side of the timepiece 9, a rock arm 4st which is of electrically conductive material and which is electrically connected with the time-piece 9. The rock arm et-it has rotatively mounted on it a roller 45 of insulating material, which is adapted, when the rock arm 44: swung by the operation of the alarm part of the timepiece 9, from the position shown in Figs. 3 and T to the posi tion shown in Fig. 8, to engage with and swing the lever St to a position in which the holding latch 30 will move to a position in which the rack bar 29 will be released from the projection 32 011 said latch bar, providing the rack bar has previously been moved to the upper position shown in Fig. 7. For closing the circuits in which the dynamo is located at the time the lever 3% is moved to the position shown in Fig. 8, there is 5' cured to the rear side of the plate 6 a contact spring l6, which is electrically connected to the plate (3 and is adapted to be struck by the rock arm -lljust prior to the time the roller l5 engages the lever 3t. The plate 6, rack bar 29, stud 38, and cover 3. are all electrically connected with each other and form the ground for the working circuit and the branch circuit employed for short-circuiting the generator 15.

Secured at one end to the stud 38, is a cont act spring 47, which carries a contact 48, which is adapted to rub against a stationary vertical contact plate 49, during the initial part of the downward vertical movement of the rack bar 29. The contact plate 49, as shown in Figs. 1, 3 and 4, is secured to a vertical plate 50, by means of screws 51 and 52, said screws being insulated from the plate 50 by insulating washers 53, the plate 49 being insulated from the plate 50 by a strip of insulating material 54. Secured to the plate 50, below the contact plate 49, is a plate 55, which is insulated from the plate 50 by the insulating strip 54. The plate 55 is provided for the purpose of supporting the traveling contact 48, after said contact has passed off from the lower end of the plate 49 during the downward move ment of the rack bar 29.

For the purpose of normally moving the lever 34 to the position shown in Figs. 3 and 7, any desired means may be employed. To accomplish this I have illustrated in the drawings a fiat spring 56, one end of which is secured to a horizontal stud 57, mounted in the plate 6 and the other end of which bears against the lever 34 below the pivot pin 35. For the purpose of drawing the rack bar 29 upward into engagement with the projection 32 of the latch bar 30, any suitable means may be employed. For this purpose I have designed a setting key, shown in Fig. 5, comprising a straight rod 58, one end of which is screw threaded and adapted to be inserted in and fit a threaded vertical hole in the upper end of the rack bar 29. The opposite end of the setting key 58 may be provided with a squared reccss 59, adapted to receive the square ends of the arbors 10, 11., 12 and 13. The bar 58 may be provided with a transverse finger hold (30 by which the rod may be drawn lei'igthwise for drawing up the rack bar 29 or rotated for turning the arbors 10, 11, 12 and 13. The cover 3 is preferably pro vided with a vertical hole 61, through which the setting key 58 may be inserted when it is to engage the rack bar 29. A closure 62 may be pivoted to the upper side of the cover 3 for the purpose of normally closing the hole 61.

The forward side of the casing 2 is provided with an observation opening 63, which is covered by a transparent plate 64 and which is located in a position such that the face of the time-piece 9 may be seen when the working parts are mounted in the easing 2. The rear side of the casing 2 is provided with suitably located holes 65, 66, (37 and 68, through which the setting key 58 may be inserted for the purpose of turning the arbors 10, 11, 1.2 and 13 respectively.

To reduce the impact of the rack bar 29, I preferably mount upon the top of the base plate 5 a vertical coil spring 69, shown in Fig. 1, which is adapted to receive upon its upper end the lower end of said rack bar. For locking the cover 3 to the outer casing 1, said cover may have secured to it a staple which is adapted to extend through a hasp 71, pivoted to the outer casing 1. The staple is adapted to receive therein the shackle 72 of a lock 73, as shown in Fig. 10.

I will now describe the preferable arrangement of circuits in which the genera tor 15 is located z-Secured to the field coil 16, is a conductor 74, which is electrically connected to the timepiece 9. The other field coil 17 is connected by a conductor 7 5 to a binding post 7 6,. which is mounted in but insulated from the cover 3. Said binding post is connected by a conductor 77 with the screw 52, which is in electrical contact with the extended contact plate 49. The binding post 76 has connected to it also a conductor 78 which is connected to a fuse wire 79, connected to the charges 80, which are provided with the usual electric fuse exploders or spaced terminals. Said fuse wire 79 is connected by a conductor 81 to a binding post 82, which is secured to and is electrically connected with the cover 3.

I will now describe the operation of my invention :After the charges 80 have been properly placed and are ready to be exploded, the conductors 78 and 81 are connected respectively to the binding posts 76 and 82, and also to the terminals of the fuse wire 79. The lock 73 may then be removed from the staple 70 from which the hasp 71 is then removed. The cover 3 and inner casing 2 may then be withdrawn from the outer casing 1, and set in the position which they are to occupy when the charges are exploded. The parts will now be in the position shown in Fig. 8. In this position the branch circuit which passes through the extended contact plate 49 will be broken, the contact 48 rest-ing upon the plate 55. The setting key 58 is then applied to the arbors 10, 11 and 12 for winding the time spring and for setting the time and alarm hands in the usual manner. The setting key 58 is then inserted through the hole 61 in the cover and is engaged with the rack bar 29. By pulling the setting key 58 upward the rack bar 29 will engage the projection 32 of the latch bar 30, the rack arm 44 having previously been turned from the position shown in. Fig. 8 to the position shown in solid lines in Fig. 7. In this position of the parts it will be noted that the circuit is broken between the rock arm 44 and the spring 46, so that if by jarring or other rough usage the lever 34 is swung to release it the time that the alarm side of the timepiece operates the arbor 13 will. turn in the usual manner, thereby swinging the rock arm 44: against the spring and immediately afterward the insulating roller 45 will strike the lever 34; and force it to the position shown in dotted lines in Fig. 7, which is assumed to be the position occupied by said lever when the latch bar 30 releases the rack bar 29. it this time the rack bar 29 will be forced suddenly downward by the spring 36, thereby rotating the armature shaft 18 in the manner hereinbefore described, thus causing the generator 15 to develop a current which will flow through the branch circuit by the following described path :-Starting from the field coil 1. the current will flow through the conductor 75 to the binding post '76, thence through the conductor 77, screw 52, contact plate e9, traveling contact lS, spring a7, stud 38, rack bar 29, plate (3, contact spring so, rock arm H, time piece 9, conductor 7%, field coil 16, brush 20, commutator 19 and armature winding connected therewith, and brush 21, back to field coil 17. This branch circuit having the least resistance of the two circuits will receive therethrough the bulk of the current developed by the generator. By the time the contact 48 has reached the lower end of the contact plate t9 the generator will have developed a maximum of elliciency. The current 48 is so arranged that it will pass off from the contact plate 49 before the rack bar 29 has reached the limit of its downward movement. As soon as the contact 48 passes off from the contact plate t9 the current will pass from the field coil 17 through the conductor 70, binding post 76, conductor 78, and fuse wire 79, to and through the charges 80, thence through the conductor 81 to the binding post 82. From the binding post 82 the current will pass through the cover 3, plate 6, spring tti, rock arm at, time piece 9, and from thence by the path already described, back to the field coil 17. At this time the parts will be in the position shown in Fig. 8. After the branch circuit containing the contacts Q8 and L9 has been broken. the current being fully built up will pass with a surge of maximum volume and intensity through the working circuit just described, and will cause with certainty, the explosion of all the charges located in said circuit. As the rack bar 29 moves downward, the stud 38 will strike the upper downwardly inclined edge of the projection 43 on the latch 39, thus moving said latch and the lever 34: to the left, as viewed in Fig. 8, a distance SUHlcient for the passage of the stud 38 past the projection %3, the spring forced arm llyielding sufficiently to permit such movement of said latch and lever.

As the mechanism is inclosed in the inner casing 2 through which access can be had to the working parts only by use of the special setting key 58, a person not possessing such a key can not cause a current to pass from the generator over the working circuit and thereby cause a premature explosion. \Vith the parts disposed as shown in Fig. 8, the

rack bar 29 cannot be lifted by reason of its engagement with the locking latch 89. In the position of the parts shown in Fig. 7 the working circuit cannot be completed until the operation of the alarm has taken place at the time set. Even if the mechanism is jarred so as to release the rack bar 29 from the latch 30 the generator will be operated but will produce no current for the reason that the rock arm 44 in the position shown in solid lines in said figure, is out of contact with the spring 46 and both the branch and working circuits are thus broken. After the mechanism has been set so as to effect an explosion at a pre-detcrmined time, it is placed with the inner casing 2 within the outer casing 1, which is then locked, by the mechanism already described, to the cover 3. The apparatus may then be set in any suitable position and safely left, until it has operated to effect the explosions of the charges with which it is connected.

It will be noted that the circuit controlling contacts all have a rubbing contact so that perfect electrical. connection is always effected and the full effect of the current is obtained. The employment of the outer casing 1 not only insures against ui'iauthorized manipulation but it protects the working mechanism from injury by the access thereto of moisture or dirt.

Various modifications of my invention, within the scope of the appended claims, may be made without departing from its spirit.

Having thus described my invention, what I claim and desire to secure by Letters Patent, is

1. In means for exploding charges, a mechanical generator of electricity located in a working circuit, means for operating the generator, means for short circuiting the generator during the initial part of its operation, means for locking the operating means against movement to the operative position, and time controlled means controlling the operation of the locking means.

2. In means for exploding charges, a

mechanical generator of electricity located in a working circuit, means for operating the generator, means for locking the operating means against movement into the operative position, a time piece, and means controlled by the time piece for controlling the locking means.

3. In means for exploding charges, a mechanical generator of electricity located in a working circuit, means for operating the generator, and time controlled means for locking the operating means against move ment to the operative position and for controlling passage of current through said circuit.

4. In means for exploding charges, a mechanical generator of electricity, means for operating the generator, means for holding the operating means inactive when in the operative position, a latch for holding the operating means from movement into the operative position, and time controlled means for releasing the holding means.

5. In means for exploding charges, a mechanical generator of electricity, means for operating the generator, means for holding inactive the operating means when in the operative posit-ion, a latch for holding the operating means from movement into the operative position, and time controlled means for releasing the holding means and operating the latch.

6. In means for exploding charges, a mechanical generator of electricity, means for operating the generator, means for holding the operating means inactive when it has been moved into operative position, a latch for holding the operating means from movement into the operative position, and time controlled means for controlling said circuit, releasing the said operating means and operating said latch.

7. In means for exploding charges, a current generating means, circuit controlling means in circuit with said generating means, means for operating said circuit controlling means, a time piece, and means controlled by the time piece for setting into operation the said operating means and for locking the operating means against movement into operative position.

8. In means for exploding charges, a current generator, circuit controlling means in circuit with said generator, means for operating said controlling means, means for holding the operating means inactive when it has been moved into the operative position, means for locking the operating means from movement into the operative position, and time controlled means for closing said circuit and operating the holding and looking means.

9. In a means for exploding blast charges, a mechanical generator of electricity, means for actuating said generator, a latch for holding the actuating means against movement in the active direction, a circuit closer in the circuit of the generator, and time controlled means for closing the circuit and subsequently releasing the generator actuating means to active movement.

10. In a device of the character described, a mechanical generator of electricity, a train of gear for actuating the same, a longitudinally movable rack bar engaging said train of gear and active to the same in one direc tion, a spring for impelling the rack bar actively, a latch for holding the rack bar against the action of its spring, a lever carrying the latch, a time piece, means carried by the time piece for moving the lever in a direction to unlatch the rack bar, and a contact in the generator circuit co-acting with the time piece impelled means to complete the generator circuit prior to the act-uation of the lever.

11. In a device of the character described, a time piece of the alarm clock type, a mechanical generator of electricity, a spring actuated means for actuating the generator, a latch for holding the generator impelling means against action when its spring is under tension, an arm carried by the alarm side of the time piece and included in the generator circuit, means under the control of the arm for releasing the generator-actu ating means, and a contact in the generator circuit in the path of the arm and engaged thereby prior to the unlatching of the generator-actuating means.

In testimony whereof I have signed my name to this specification in presence of two subscribing witnesses.

CHARLES I. DODSON.

Witnesses WARREN D. House, E. B. HOUSE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

